用硫普罗宁(tiopronin,TP)作为稳定剂,在水相中合成了荧光发射波长可调的高荧光CdTe量子点。本文详细地研究了稳定剂与Cd之比和DH值等实验条件对CdTe纳米粒子体系的荧光量子产率的影响。在pH=11.3回流2h,纳米粒子体系在537nm波长处的荧光量子产率达到了66%。通过控制实验条件,合成了各种尺寸的CdTe量子点,荧光发射光谱在504—602nm范围连续可调。分别用X射线光电子能谱(XPS)、透射电子显微镜(TEM)、X射线衍射(XRD)、红外吸收光谱(FTIR)表征了CdTe粒子的分散性、形貌和晶型。溶血实验显示,这些由硫普罗宁稳定的CdTe量子点几乎不发生溶血作用(溶血率低于5%),具有良好的生物相容性。
The water-soluble CdTe quantum dots have been synthesized by using tiopronin (TP) as stabilizer in aqueous solution at 100 ℃. The experimental results demonstrate that several parameters including pH and molar ratios of the TP ligands to the concentration of Cd^2+ ions in the precursor solution play an important role in the photoluminescence(PL) quantum yield(QY) of the as-prepared CdTe quantum dots(QDs). Refluxing for 2 h at pH= 11.3, the maximum PL QY of the obtained CdTe QDs at 537 nm is 66% at room temperature without any postpreparative treatment. By controlling the reflux time, CdTe quantum dots with various sizes can be obtained in aqueous solution. The room-temperature PL emission spectrum of CdTe quantum dots in aqueous solution covers the spectral region from 504 to 602 nm with a maximum located at 537 nm. TEM, XRD, XPS and FTIR spectroscopy are used to characterize the size, shape, and composition of the CdTe nanocrystals. The hemolysis assay shows that the TP-capped CdTe quantum dots have good bioeompatibility.